1. Field of the Invention
Aspects of the present invention relate generally to an image revising method, an image forming apparatus, and a method for revising an image spreading. More particularly, aspects of the present invention relate to an image revising method and an image forming apparatus for enhancing a copy quality of a document including a black color, and a method for revising an image spreading.
2. Description of the Related Art
Generally, a copy process incorporates a scanning process and a printing process. In the copy process, there are two factors which deteriorate the image quality. One factor is hardware fault, that is, misregistration error of the Cyan, Magenta, Yellow and Key (CMYK) color model because of defects in a scanner motor and a printer engine, and the other factor is mismatch of black points when a printer uses a lookup table. When the misregistration error occurs in copying a document having black text, legibility of the black text deteriorates and the consumption of cyan, magenta, and yellow inks increases against the consumption of the black ink. As a result, the yield of the ink (or the toner) is problematic.
To raise the legibility of the black text, a conventional method emphasizes the black text by intensifying the black offset in a 1D lookup table. However, the conventional method for intensifying the black offset causes the problem in the ink yield and hardly addresses the misregistration error.